1. Field of the invention
The present invention relates to an adjustable-brush electric machine having a variable commutating angle, and more particularly, to a motor incorporating a stepping motor or servo for electromechanically adjusting the brushes.
2. Description of the Background
It is well-known that the commutating angle of an electric machine can be altered by rotating the brushes relative to the commutator. This concept can be implemented to reduce sparking at the brushes due to sudden load changes. In addition, it is a convenient technique for reversing the direction of rotation of the motor. However, the rotation of the motor makes it quite difficult to implement an accurate means for shifting the brush position relative to the commutator.